The invention relates generally to the field of oral care, and in particular to toothbrushes.
A Japanese patent document having an application number of 3-312978 discloses a toothbrush having a multiplicity of tufts of nylon bristles. In a first embodiment shown in FIGS. 1, 2 and 3, a plurality of cylindrical recessed sections in the head are set orthogonally to the longitudinal axial direction of a shank and are formed at equal intervals. Column-shaped rotary bodies 5 are respectively contained in the recessed sections. On the peripheral surfaces of the rotary bodies 5, along the axial direction, projected strip sections 5a are formed, and they are set in a state that they are positioned at the opening sections of the recessed sections. At the opening sections of the recessed sections, contact surfaces to be positioned on both the sides are formed. At both the ends of the upper surfaces of the projected strip sections 5a, nylon bristles 6 are arranged to be vertically erected.
As shown in FIG. 3, the arrangement described above allows bristles 6 to rotate during use of the brush. A problem with this brush is that two tufts of bristles are secured to each strip section 5a and thus must rotate in unison. As a result, an individual tuft of bristles cannot rotate independently of its xe2x80x9cpartnerxe2x80x9d tuft. The individual tuft may thus be prevented from achieving optimal penetration between two teeth during brushing because the partner tuft might contact the teeth in a different manner and interfere with rotation of the individual tuft.
FIGS. 4, 5 and 6 disclose a second embodiment in which each tuft of bristles is secured to the head by a ball and socket type arrangement. While this embodiment allows each tuft of bristles to swivel independent of the other tufts, it does have disadvantages. If a tuft of bristles is tilted out towards the side of the head and that tuft is positioned near the interface between the side and top surfaces of the teeth, chances are increased that the bristle tips will not even be in contact with the teeth during brushing. Further, random orientation in which the tufts can end up after brushing detracts from the attractiveness of the brush.
The present invention is directed to overcoming one or more of the problems set forth above. Briefly summarized, according to one aspect of the present invention, a toothbrush includes a handle, a head extending from the handle, and a plurality of tooth cleaning elements, such as tufts of bristles, extending from the head. Each tooth cleaning element is supported for rotation about primarily only one axis. Each tooth cleaning element is rotatable independent of the other tooth cleaning element(s).
By having each tooth cleaning element supported for rotation about only one axis, the problems mentioned above for the ball and socket tuft support are avoided. That is, the chances are increased that the tooth cleaning element will remain in contact with teeth during brushing and the brush will be more attractive in appearance.
Further, as each tooth cleaning element is rotatable independent of the other tooth cleaning element(s), the problem discussed above with the first Japanese embodiment is avoided. Each tooth cleaning element can achieve optimal interdental penetration without interference from rotation by another tooth cleaning element.
These and other aspects, objects, features and advantages of the present invention will be more clearly understood and appreciated from a review of the following detailed description of the preferred embodiments and appended claims, and by reference to the accompanying drawings.